Portable electronic device

Abstract

Electronic devices, such as mobile communication devices, may include several enhancements and modification not found on traditional electronic devices. An electronic device can include a circuit board assembly that includes stacked layers of circuit components that are retained in a stacked configuration and operably connected to each other by retention features such as solder joints. Features can be provided for structural support and thermal mitigation. A battery assembly can accommodate nesting of other components, such as display components, within one or more recesses defined by variable thickness along different regions of the battery assemblies. The battery assembly can further provide a slim profile by including notches to accommodate the increased thickness of a pouch having folded flaps to seal a cell module of the battery assembly.

What is claimed is: 
     
       1. A circuit board assembly for an electronic device, the circuit board assembly comprising:
 a circuit component; 
 a first stiffener extending along a first surface of the circuit component; 
 a cover extending along a surface of the first stiffener; and 
 a second stiffener extending along a second surface of the circuit component, adjacent to the first surface, the second stiffener comprising an inner layer comprising a first metal and outer layers comprising a second metal. 
 
     
     
       2. The circuit board assembly of  claim 1 , wherein the outer layers have a higher rigidity than a rigidity of the first metal. 
     
     
       3. The circuit board assembly of  claim 1 , wherein the first metal has a higher thermal conductivity than the second metal. 
     
     
       4. The circuit board assembly of  claim 1 , wherein the second stiffener has a higher rigidity than a rigidity of the first stiffener and cover. 
     
     
       5. The circuit board assembly of  claim 1 , wherein the second stiffener is positioned on a portion of the circuit component that is not covered by the first stiffener and the cover. 
     
     
       6. The circuit board assembly of  claim 1 , wherein the first stiffener comprises the second metal. 
     
     
       7. The circuit board assembly of  claim 1 , wherein the second stiffener is adjacent to the first stiffener and the cover. 
     
     
       8. A circuit board assembly for an electronic device, the circuit board assembly comprising:
 a substrate; 
 a circuit component on the substrate; 
 a trace connected to the circuit component and extending along a surface of the substrate; and 
 multiple vias extending from the trace and forming a non-linear pathway through the substrate. 
 
     
     
       9. The circuit board assembly of  claim 8 , wherein the trace extends about an opening extending through the substrate, the opening being configured to receive a fastener to secure the circuit board assembly to a housing. 
     
     
       10. The circuit board assembly of  claim 8 , wherein each of the vias comprises segments each at a different depth away from the trace, each of the segments extending along a different axis that intersects a different portion of the trace. 
     
     
       11. The circuit board assembly of  claim 8 , wherein each of the vias extends through multiple conductive layers beneath the surface of the substrate. 
     
     
       12. The circuit board assembly of  claim 8 , wherein at least some of the vias extend outside a region of the substrate that is beneath the circuit component. 
     
     
       13. An electronic device comprising:
 a battery assembly comprising a battery circuit component having a first portion with a first thickness and a second portion with a second thickness less than the first thickness and defining a recess; and 
 a display assembly comprising a display circuit component protruding into the recess defined by the battery circuit component. 
 
     
     
       14. The battery assembly of  claim 13 , wherein the display assembly comprises a display surface that extends over an entirety of the battery assembly. 
     
     
       15. The battery assembly of  claim 13 , wherein the display circuit component is nested within a region partially surrounded by the battery circuit component. 
     
     
       16. The battery assembly of  claim 13 , wherein the display circuit component is a battery protection circuit module. 
     
     
       17. A battery assembly comprising:
 a cell module comprising a first edge and a second edge that are connected by a cell notch in the cell module; and 
 a pouch comprising a first flap folded over the first edge toward the cell module and a second flap folded over the second edge toward the cell module, the first flap and the second flap being connected to each other over the cell notch of the cell module. 
 
     
     
       18. The battery assembly of  claim 17 , wherein the cell notch is formed at an interior corner of the cell module. 
     
     
       19. The battery assembly of  claim 17 , wherein the first flap and the second flap are connected by a pouch notch that is formed over the cell notch in the cell module. 
     
     
       20. The battery assembly of  claim 17 , further comprising a tape member covering at least a portion of the first flap, the second flap, and the cell notch.